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https://www.ck12.org/book/ck-12-middle-school-math-concepts-grade-7/section/10.2/ https://www.ck12.org/book/ck-12-middle-school-math-concepts-... > An edge is
by neogodless 5y ago
https://www.ck12.org/book/ck-12-middle-school-math-concepts-grade-7/section/10.2/ https://www.ck12.org/book/ck-12-middle-school-math-concepts-...
> An edge is the place where two faces meet. Edges are straight; they cannot be curved.
> Cones, spheres, and cylinders do not have any edges because they do not have any flat sides.
- dghf 5y agoCones and cylinders don't have any flat sides?
- dylan604 5y agoNo wonder US schools are so poorly rated. They get very basic stuff very wrong like this. 2+2=5 is probably in the previous chapter.
- junon 5y ago2.4 rounded is 2. 2.4 + 2.4 = 4.8, rounded is 5. Therefore, 2 + 2 = 5. I was taught this as a "mind teaser" in middle school once. It was supposed to be cute and fun, but just ended up confusing half the class.
- dghf 5y ago2 + 2 = 5, for sufficiently large values of 2 and sufficiently small values of 5.
- deleted 5y ago[deleted]
- hulitu 5y agoTalking about undefined behaviour.
- xook 5y agoCute and fun, but also very real if you're a CPU: https://0.30000000000000004.com/ https://0.30000000000000004.com/
- junon 5y agoI wouldn't consider the brain teaser a result of FP error. But yes, something to consider anyway.
- handrous 5y agoWebster's 1913: 2. Any sharp terminating border; a margin; a brink; extreme verge; as, the edge of a table, a precipice. 4. The border or part adjacent to the line of division; the beginning or early part; as, in the edge of evening. "On the edge of winter." Milton. Either the literal sense 2 or figurative sense 4 works here. The special mathematical sense is nowhere given in that edition of Webster's. I suppose they expected one would consult Euclid if one wished to know its sense in that jargon.
- neogodless 5y agoPerhaps we should just change the title to say an edge of the Earth?